[RatFarmer]

I've heard several times that you are not supposed to combine cardio and strength training on the same day (and if you must, do cardio last). Is there a reason for this? Does it have to do with resting the muscles after strength training for maximum gain?
I'm time challenged, so I occasionally have to do both on the same day.

 

[bbmj]

it is best to train on seperate days, and if you do train on same day, cardio second,
from Science and Practice of Strength Training-
"Such strength training is even more difficult to combine in training programs with endurance type of activity. The demands of the two types of activity are different. heavy resistance training, for example, stimulates muscle fiber hypertrophy, which reduces capillary density and mitochondrial volume in the working muscles. These changes are detrimental to endurance. Endurance training in contrast, elicits an increase in capillary density and mitochondrial volume and density and may cause a decrease in muscle fiber size. When strength and endurance training are done concurrently, it is difficult for an organism to adapt simultaneously to the conflicting demands. Consequently, the combination of endurance and strength training impairs strength gains in comparison to strength training alone. This is also true with respect to endurance training. As the time between the two types of exercise lessens, the impediment becomes greater. SAME DAY TRAINING, FOR INSTANCE, IMPEDES DEVELOPMENT TO A GREATER EXTENT THAN DOES TRAINING ON ALTERNATE DAYS. Another factor that influences the interference is the magnitude of hte training load;the greater the load, the more incompatible strength training is with endurance training."

this is from the mouth of a PhD, and hte strength and conditioning coach of the Russian olympic teams, so it is pretty accurate. hope this helps.

 

[RatFarmer]

That's exactly what I wanted to know. Thanks bbmj!

 

[bbmj]

no prob, glad to help a fellow monkey.
charlie

 

[MtnBikerChk]

More simply - after you work your muscles, your body is depleted and needs protein. If you do cardio right after, you won't have anything for your body to use for energy so it uses (some fat) the protein - which robs the muscles you are trying to build.